<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        div{
            width: 343px;
            height: 150px;
            margin: 100px auto;
            border-radius: 10px;
            background: url("img/paopao.png") no-repeat left top,
                        url("img/paopao.png") no-repeat right bottom;
            background-color: red;
            transition: all 2s ease-in-out;
        }

        div:hover{
            background: url("img/paopao.png") no-repeat left  bottom,
                        url("img/paopao.png") no-repeat right top;
            background-color: red;
        }
    </style>
</head>
<body>
    <div></div>
</body>
</html>